Lifting-jack.



O. E. LOETZER 6: W. T. GOODNOW.

LIFTING JACK. APPLICATION FILED JULY 22, 1909.

Patented Sept.27',1910.

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CHRISTIAN E. LOETZER AND WILLIAM T. GOODNOW, 0F SAYRE, PENNSYLVANIA;SAID LOETZER ASSIGNOR TO SAID GOODNOW.

LIFTING-JACK.

To all whom "it may concern:

Be it known that we, CHRISTIAN E. LOETZER and XVILLIAM T. GOODNOW,citizens of the United States, residing at Sayre, in the county ofBradford and State of Pennsylvania, have invented certain new and usefulImprovements in Lifting-Jacks, of which the following is aspecification.

This invention relates to improvements in screw operated jacks whereinthe screw is mounted in a nut fastened in a hollow stand, and motion istransmitted to a load carry ing sleeve, which telescopes upon the stand,through a thrust bearing at the top of the screw.

Our objects are to provide an improved drive for the lifting screw; andto combine therewith means for imparting a more rapid motion to thescrew when adjusting the ack to and from the load, and when operating onlight loads.

A further object is to improve the construction of the jack in certaindetails which will hereafter be more particularly pointed out andspecified in the claims.

e attain our objects by constructing the jack in the manner illustratedin the accompanying drawings, in which Figure 1 represents a verticalsection through the ack; Fig. 2, a side elevation of the upper portionof the jack; Fig. 3, a transverse section on the line aa in Fig. 2; andFig. 41-, a plan view of the upper end of the jack.

Like numerals designate like parts in the several views.

Upon the stationary stand 1 is mounted a telescoping sleeve 2, providedat 3 with an enlargement to form a chamber in which is contained theoperating mechanism. This chamber is separated from the sleeve by adiaphragm 1, centrally bored to permit the passage therethrough of thescrew lVherc the screw passes through the (liaph 'agni we provide astutling box 6, having a packing gland 6 so that oil or grease may beplaced in the chamber, and its leakage downward past the screwprevented. The stand, at its upper end, has a. nut 7 of suitable metal,preferably bronze, fastened therein, which receives the lifting screwThe upper end of the screw has keyed to it a worm wheel 8, the upperportion of which wheel is carried out somewhat at 10 to form a supportfor the ball bearing through which motion Specification of LettersPatent.

Application filed July 22, 1909.

Patented Sept. 27, 1910.

Serial No. 508,997.

is transmitted from the screw to the sleeve. This ball bearing consistsof two grooved rings 9, of hardened steel, between which the balls arelocated, the lower ring resting upon the worm wheel, and being centeredby the upward extension of the screw shaft. The upper ring is alsocentered by the screw shaft, and upon it rests a cap piece 12, which isadapted to close an opening 11 through the upper end of the sleeve, saidopening being provided with an inturned flange 11 which is engaged by ashoulder 12 on the cap piece, so that the thrust from the screw istransmitted through the cap piece to this flange when the sleeve isbeing raised, and vice versa.

A worm 1a to operate the worm wheel is positioned at one side of thechamber 3, and is driven by a shaft 18, the thrust on said shaft, whenthe screw is operated to lift a load, being transmitted to a suitablethrust bearing contained in the journal box 15, formed within saidchamber. The shaft 13 projects at the opposite end through a bearing 16formed on the coverplate 17, which closes an opening at one side of thechamber. Inside this coverplate, the shaft is provided with a smallpinion 18, which meshes with a larger gear 19, mounted upon a shaft 20,which projects through a hearing 21 on the coverplate. The opening whichis closed by this coverplate is sufficiently large to permit theinsertion and removal of the bearing rings 9, and the cap 12, as well asthe worm and gears.

Preferably the shaft 13 and its bearing 16 will be carried out beyondthe shaft 20 and a ratchet wheel 22 and operating bar 27 will be appliedto the end of the shaft; so that, in turning the worm, the ratchet maybe operated with the bar in any position around the shaft, or may becarried completely around with the shaft, if so desired.

For use on this worm shaft we are provid ing a ratchet deviceparticularly adapted for our purpose. This device consists of theratchet wheel 22, contained in a frame 23, and having a hexagonal orother suitably shaped opening broached through it to fit a similar shapeon the worm shaft, the ratchet being held upon the shaft by means of acotter pin at 13 inserted through a hole provided therefor in theprojecting end of the shaft. The ratchet is operated in either directionby means of a pawl 24, slidably mounted in a socket formed at one sideof the ratchet frame, and held in engagement with the ratchet wheel bymeans of a coiled spring 24, as shown in Fig. 2. The stem of the pawlprojects outside of the socket, and is provided with a turning pin 25,which projects from one side of the stem only, in order that said pinmay indicate when the pawl is set to operate the ratchet to the right orleft. The ratchet frame is provided with a socket 26, through which theoperating bar 27 passes. This socket is so positioned that the bar maybe run completely through the socket, and set so as to be operated fromeither side of the jack, and with any desired leverage. As shown hereinthis socket is po sitioned above the ratchet wheel, so that the bar willpass over the worm shaft.

The shaft 20 for operating the large gear has its projecting end formedin the same manner as the shaft 13; and, if desired, the ratchet may betransferred to this shaft. As, however, it is the intention to use thisshaft for the quick adjustment of the jack, to and from the load, weprovide a socket crank, as indicated by the broken lines at 32 in Fig.3, for operating this shaft.

The top of the sleeve, or, rather, the enlargement 3, and the outwardface of the cap piece 12, are formed in any desired manner for receivingand supporting the load; and the sleeve will further be provided at itslower end with a projecting foot piece 31, to be used where the jackcannot be inserted beneath the load.

To prevent the screw from being rotated to such an extent as to carrythe sleeve above the top of the stand 1, we provide at 29 a latchsimilar to the pawl 24:; which, when the sleeve reaches its upperextension, engages a groove 28, formed around the upper end of thestand 1. The turning pin 30 in dicates the position of this latch; andit will be evident that, by reversing the position of this pin, thelatch will be turned in a position to be snapped past the groove 28 topermit the removal of the sleeve from the stand, when desired.

By means of our sleeve construction, the thrust of the screw on the ballbearing, (which bearing in itself is not new), is transmitted throughthe cap piece 12 to the flanged end of the sleeve. The sleeve isotherwise integral, and there is, therefore, no weakening screw jointsto receive the thrust, whether the load is carried upon the head of thescrew, or by the foot piece 31. Moreover, the openings at the oppositeends of the sleeve materially assist in the proper casting and machiningof the sleeve, as will be evident to those skilled in the art.

To assemble the jack, the sleeve is first placed upon the stand; thenthe screw, with the worm wheel keyed thereon, is inserted through theopening 11, and screwed down until the worm wheel strikes the packinggland for the stuffing box 6. This permits the ball bearing. rings andballs to be inserted through the side opening and placed in positionupon the worm wheel and screw shaft; after which the cap piece 12 ispassed through the side opening and placed upon the upper bearing ring.The screw is then screwed up until the cap piece enters the opening 11and engages the flange. The stufling box 6 is then packed, and the glandscrewed down to make a tight joint around the screw; after which thejack is turned over upon one side and the chamber 3 filled, or partiallyfilled, with oil or suitable lubricating grease. The coverplate 17, withthe gears and gear shaft assembled thereon, is then set in place, theworm being screwed into engagement with the worm wheel until the end ofthe shaft 13 enters the bearing 15, and the coverplate comes up againstthe face of the side opening; after which the coverplate is bolted intoplace, and the jack is ready for use. To make an oil tight joint, asuitable gasket (not shown), or other packing device, will be necessarybetween the cover-plate and the face of the side opening.

For the purpose of properly alining the shaft 13 we bore the sideopening of the chamber, where indicated by the broken lines at 33 inFig. 2, to the same center as that of the bearing 15, and provide thecoverplate at 34 with an inside boss turned to the same diameter,whereby the coverplate will be properly centered with the bearing 15when it is brought up into place; and the shaft 13 will run true in itsbearings.

By our arrangement of the worm drive for the screw, as above described,and a proper proportioning of the worm wheel and worm, and of the pinionand gear, we are enabled to materially reduce the lifting power, orenergy, to be applied to the worm shaft in raising the load, and toreduce the number of revolutions of the quick adjustment shaft for agiven lift of the screw, as compared with screw jacks now on the market.The power is to be applied directly to the worm shaft when lifting theload. Should, however, power he applied to shaft 20 when the jack isunder load to such an extent as to strip the gear teeth, the jack willstill remain in commission, since the operation of the jack under loadis independent of the gears 18 and 19. The worm also acts in itself as apositive lock for the lifting screw when the jack is under load; so thatthe screw cannot run down.

By providing the oil chamber for the operating parts, there will alwaysbe a thorough lubrication of the gears and bearings, and the worm gearwill run at all times in a bath of oil or lubricant, thereby reducingthe friction of the worm against the teeth of the worm wheel to aminimum. l ve thus facilitate the ease of operation of the jack, andprevent wear between the worm and worm wheel; which hitherto have causedtrouble in the use of a worm gear for jack purposes.

By this construction we are further enabled to materially reduce theweight of the jack for transmitting any given power; since the stand maybe made small in diameter, and the sleeve, where it telescopes upon thestand, correspondingly small, as the scre and working parts can all beassembled through the end opening 11, and the side opening to thechamber Moreover, the operating mechanism is condensed into small space,thereby reducing the size and weight of the upper parts of the sleeve.

\Vhile we have shown our jack as arranged with the quick adjustmentgear, we do not limit ourselves to this construction; since the worm andworm gear only may be used and the gears 18 and 19 omitted where quickadjustment is not required. Moreover, the opening through the diaphragm4, through which the screw 5 passes, may be arranged in any suitablemanner for retaining the oil or grease within the chamber; and we do notlimit ourselves to the stufling box construction, as shown herein by wayof illustration. The oil chamber may also be omitted and the otherfeatures of our invention retained.

What we claim as our invention and desire to secure by Letters Patent isl. A lifting jack comprising a stand, a screw mounted in a flxed nutcarried by the stand, an open topped sleeve telescoping on the stand,said sleeve being provided with an inwardly extending flange at the topthereof, a diaphragm in the sleeve above the top ofthe stand throughwhich the screw passes with an oil. tight joint, an oil containingchamber in the sleeve above the diaphragm, a cap arranged to close thetop opening and provided with a shoulder extending under said flange, athrust bearing between the screw and said cap, and means within the oilchamber for turning the screw, said means being operable from outsidethe sleeve.

2. A lifting jack comprising a stand, a screw mounted in a fixed nutcarried by the stand, an open topped sleeve telescoping on the stand,said sleeve being provided with an inwardly extending flange at the topthereof and a lateral opening adjacent the top, a diaphragm in thesleeve above the top of the stand through which the screw passes with anoil tight joint, an oil containing chamber in the sleeve above thediaphragm, a worm wheel on the upper end of the screw adapted to passthrough the top openii'ig, a cap arranged to close said opening andprovided with a shoulder extending under said flange, said cap beingadapted to be inserted through the side openin a thrust bearing betweenthe screw and the cap, a worm and shaft mounted in the oil chamber inmesh with the worm wheel, means outside the chamber for operating theshaft, and a cover-plate for the side opening.

3. A lifting jack comprising a stand, a screw mounted in a fixed nutcarried by the stand, an open topped sleeve telescoping on the stand,said sleeve being provided with an inwardly extending flange at the topthereof and a lateral opening adjacent the top, a worm wheel on theupper end of the screw adapted to pass through the top opening, a caparranged to close said opening and provided with a shoulder extendingunder the flange thereof inside the sleeve, said cap being adapted to beinserted through the side opening, a thrust bearing between the screwand the cap, a worm and shaft mounted in the sleeve in mesh with theworm wheel, means outside the sleeve for operating the shaft, and acover-plate for the side opening.

4;. A lifting jack comprising a stand, a screw mounted in a nut carriedby the stand, an open topped sleeve telescoping on the stand, saidsleeve being provided with an inwardly extending flange at the topthereof, a cap arranged to close said opening and provided with ashoulder extending under the flange thereof inside the sleeve, a thrustbearing between the screw and the cap, and means inside the sleeve forturning the screw, said means being operable from outside the sleeve.

5. A lifting jack comprising a stand, a screw mounted in a nut carriedby the stand, an open topped sleeve telescoping on the stand, saidsleeve being provided with an invardly extending flange at the topthereof and with a side opening adjacent thereto, a cap arranged toclose the top opening and provided with a shoulder extending under theflange thereof inside the sleeve, said cap being adapted to be insertedthrough the side opening, a gear wheel on the screw adapted to be passedthrough the top opening, a thrust bearing between the screw and the cap,and means operable from outside the sleeve for turning said gear wheel.

In testimony whereof we have a tlixed our signatures, in presence of twowitnesses.

CHRISTIAN E. LOETZER. \VILLIAM T. GOODNOlV. Vitnesses CHAS. C. lVns'r,Gno. E. Luce.

